[Not for review] Demo issue for discussion on https://codereview.chromium.org/2296903002/.

chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h

Index: chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h
diff --git a/chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h b/chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h
index caef203e2e30bb275279d13171c8f2408989b57a..c4d908c9ca6b54e914483f25790d5e229b2022aa 100644
--- a/chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h
+++ b/chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h
@@ -30,6 +30,13 @@ enum HiddenToolbarState {
                           // toolbarFraction is (0.0, 1.0).
 };
 
+// State of the NSMenuBAr
+enum MenuBarState {
+  MENUBAR_SHOWN = 0,
+  MENUBAR_HIDDEN,
+  MENUBAR_TRANSITIONING
+};
+
 }  // namespace fullscreen_mac
 
 // Provides a controller to fullscreen toolbar for a single browser
@@ -82,13 +89,14 @@ enum HiddenToolbarState {
   // Whether the omnibox is hidden in fullscreen.
   fullscreen_mac::SlidingStyle slidingStyle_;
 
-  // The fraction of the AppKit Menubar that is showing. Ranges from 0 to 1.
-  // Only used in AppKit Fullscreen.
+  // The fraction of the AppKit Menubar that is showing.
   CGFloat menubarFraction_;
 
-  // The state of the toolbar when the sliding style is set to
-  // OMNIBOX_TABS_HIDDEN.
-  fullscreen_mac::HiddenToolbarState hiddenToolbarState_;
+  // The state of the macOS NSMenuBar.
+  MenuBarState menubarState_;
+
+  // Whether the macOS NSMenuBar is animating in or out.
+  bool menubarAnimatingIn_;
 
   // A Carbon event handler that tracks the revealed fraction of the menu bar.
   EventHandlerRef menuBarTrackingHandler_;
@@ -96,9 +104,7 @@ enum HiddenToolbarState {
   // True when the toolbar is dropped to show tabstrip changes.
   BOOL isRevealingToolbarForTabStripChanges_;
 
-  // True when the menubar is disappearing/gone and the toolbar should still be
-  // shown. Set to false after the toolbar hides.
-  BOOL shouldShowToolbarWithoutMenu_;
+  BOOL wasToolbarShowingWhenMenubarStartedAnimatingIn_;
 }
 
 @property(nonatomic, assign) fullscreen_mac::SlidingStyle slidingStyle;